The present invention refers to a roof vent pipe with mouth-side rib structure (G) formed at least in part of annularly extending spokes, and above same a cover cap (2) which is locked via downward directed projections to an upper pipe end.
In one roof vent pipe of this type which is available on the market, three projections arranged at an equal angle apart extend from the cover of the cover cap. They are seated in the vicinity of the edge and grip below a peripheral annular rib on the mouth-side grid structure of the roof vent pipe. The supporting is effected via ledges which are developed directly on the projections. Viewed in cross-section, there is thus a T-profile of the projection shaft. The actual support is formed by the downward directed front end of the web. This development is disadvantageous since the webs which are formed o the shaft of the projections dampen the resiliency which is important for the attachment. This results in a rather hard detent behavior which, in the most unfavorable case, may even lead to a breaking off of the mating detent means, i.e., annular rib, of the grid structure. If a greater tolerance range is taken as basis, this can, in the event of a storm, lead to a lifting off of the cover cap, resulting in damage to persons or property.